DBGrid的选中问题？急！！(50分)

如何通过点击一个按钮将dbgrid中的记录全部选中？？

procedure TForm1.DBGrid1DblClick(Sender: TObject);
var i:integer;
begin
table1.First;
for i:=0 to table1.RecordCount-1 do
begin
dbgrid1.SelectedRows.CurrentRowSelected:=true;
table1.Next;
end;
end;

接受答案了.